People often carry mobile devices to venues such as office buildings, stadiums or shopping centers. In a venue, various walls, doors, hallways or stairs limit people's movement. A mobile device can display a map of a venue and a location of the mobile device on the map, if the mobile device has the map and can determine the location. A mobile device may visit many venues. Storing maps including detailed structural information of venues that the mobile device may visit on the mobile device can take up much resource on the mobile device. Downloading venue information for each venue in real time when the mobile device visits that venue may be impractical. This can be due to unreliable wireless data transmission or high cellular data transmission cost.